Posts tagged personality traits
Articles and news from the latest research reports.
Worry, jealousy, moodiness linked to higher risk of Alzheimer’s in women
Women who are anxious, jealous, or moody and distressed in middle age may be at a higher risk of developing Alzheimer’s disease later in life, according to a nearly 40-year-long study published in the October 1, 2014, online issue of Neurology®, the medical journal of the American Academy of Neurology.
"Most Alzheimer’s research has been devoted to factors such as education, heart and blood risk factors, head trauma, family history and genetics," said study author Lena Johannsson, PhD, of the University of Gothenburg in Gothenburg, Sweden. "Personality may influence the individual’s risk for dementia through its effect on behavior, lifestyle or reactions to stress."
For the study, 800 women with an average age of 46 were followed for 38 years and given personality tests that looked at their level of neuroticism and extraversion or introversion, along with memory tests. Of those, 19 percent developed dementia.
Neuroticism involves being easily distressed and personality traits such as worrying, jealousy or moodiness. People who are neurotic are more likely to express anger, guilt, envy, anxiety or depression. Introversion is described as shyness and reserve and extraversion is associated with being outgoing.
The women were also asked if they had experienced any period of stress that lasted one month or longer in their work, health, or family situation. Stress referred to feelings of irritability, tension, nervousness, fear, anxiety or sleep disturbances. Responses were categorized as zero to five, with zero representing never experiencing any period of stress, to five, experiencing constant stress during the last five years. Women who chose responses from 3 and 5 were considered to have distress.
The study found that women who scored highest on the tests for neuroticism had double the risk of developing dementia compared to those who scored lowest on the tests. However, the link depended on long-standing stress.
Being either withdrawn or outgoing did not appear to raise dementia risk alone, however, women who were both easily distressed and withdrawn had the highest risk of Alzheimer’s disease in the study. A total of 16 of the 63 women, or 25 percent, who were easily distressed and withdrawn developed Alzheimer’s disease, compared to eight out of the 64 people, or 13 percent, of those who were not easily distressed and were outgoing.
(Image: Corbis)
Researchers Debunk Myth of “Right-brain” and “Left-brain”Personality Traits
Newly released research findings from University of Utah neuroscientists assert that there is no evidence within brain imaging that indicates some people are right-brained or left-brained.
Chances are, you’ve heard the label of being a “right-brained” or “left-brained” thinker. Logical, detail-oriented and analytical? That’s left-brained behavior. Creative, thoughtful and subjective? Your brain’s right side functions stronger —or so long-held assumptions suggest.
But newly released research findings from University of Utah neuroscientists assert that there is no evidence within brain imaging that indicates some people are right-brained or left-brained.
For years in popular culture, the terms left-brained and right-brained have come to refer to personality types, with an assumption that some people use the right side of their brain more, while some use the left side more.
Following a two-year study, University of Utah researchers have debunked that myth through identifying specific networks in the left and right brain that process lateralized functions. Lateralization of brain function means that there are certain mental processes that are mainly specialized to one of the brain’s left or right hemispheres. During the course of the study, researchers analyzed resting brain scans of 1,011 people between the ages of seven and 29. In each person, they studied functional lateralization of the brain measured for thousands of brain regions —finding no relationship that individuals preferentially use their left -brain network or right- brain network more often.
“It’s absolutely true that some brain functions occur in one or the other side of the brain. Language tends to be on the left, attention more on the right. But people don’t tend to have a stronger left- or right-sided brain network. It seems to be determined more connection by connection, ” said Jeff Anderson, M.D., Ph.D., lead author of the study, which is formally titled “An Evaluation of the Left-Brain vs. Right-Brain Hypothesis with Resting State Functional Connectivity Magnetic Resonance Imaging.” It is published in the journal PLOS ONE this month.
Researchers obtained brain scans for the population they studied from a database called INDI, the International Neuroimaging Data-Sharing Initiative. The participants’ scans were taken during a functional connectivity MRI analysis, meaning a participant laid in a scanner for 5 to 10 minutes while their resting brain activity was analyzed.
By viewing brain activity, scientists can correlate brain activity in one region of the brain compared to another. In the study, researchers broke up the brain into 7,000 regions and examined which regions of the brain were more lateralized. They looked for connections — or all of the possible combinations of brain regions — and added up the number of connections for each brain region that was left- lateralized or right-lateralized. They discovered patterns in brain imaging for why a brain connection might be strongly left- or right-lateralized, said Jared Nielsen, a graduate student in neuroscience who carried out the study as part of his coursework.
“If you have a connection that is strongly left- lateralized, it relates to other strongly lateralized connection only if both sets of connections have a brain region in common,” said Nielsen.
Results of the study are groundbreaking, as they may change the way people think about the old right-brain versus left-brain theory, he said.
“Everyone should understand the personality types associated with the terminology ‘left-brained’ and ‘right-brained’ and how they relate to him or her personally; however, we just don’t see patterns where the whole left-brain network is more connected or the whole right-brain network is more connected in some people. It may be that personality types have nothing to do with one hemisphere being more active, stronger, or more connected,” said Nielsen.
Study finds night owls more likely to be psychopaths
People who stay up late at night are more likely to display anti-social personality traits such as narcissism, Machiavellianism, and psychopathic tendencies, according to a study published by a University of Western Sydney researcher.
Dr Peter Jonason, from the UWS School of Social Sciences and Psychology, assessed over 250 people’s tendency to be a morning- or evening-type person to discover whether this was linked to the ‘Dark Triad’ of personality traits.
The results, published in Personality and Individual Differences, found students who were awake in the twilight hours displayed greater anti-social tendencies than those who went to bed earlier.
“Those who scored highly on the Dark Triad traits are, like many other predators such as lions and scorpions, creatures of the night,” he says.
"For people pursuing a fast life strategy like that embodied by the Dark Triad traits, it’s better to occupy and exploit a lowlight environment where others are sleeping and have diminished cognitive functioning."
Dr Jonason says there may be an evolutionary basis for the link between anti-social behaviour and a preference to being awake late at night.
“There is likely to be a co-evolutionary arms race between cheaters and those who wish to detect and punish them, and the Dark Triad traits may represent specialized adaptations to avoid detection,” he says.
“The features of the night - a low-light environment where others are sleeping - may facilitate the casual sex, mate-poaching, and risk-taking the Dark Triad traits are linked to.”
“Indeed, most crimes and most sexual activity peak at night, suggesting just such a link.”
Dr Jonason adds that far more work is needed, but these results represent an important advance in behavioural ecological and evolutionary psychological models of the Dark Triad, as well as ‘darker’ aspects of human nature and personality.
China’s One-Child Policy Affects Personality
In 1979 China instituted the one-child policy, which limited every family to just one offspring in a controversial attempt to reduce the country’s burgeoning population. The strictly enforced law had the desired effects: in 2011 researchers estimated that the policy prevented 400 million births. In a new study in Science, researchers find that it has also caused China’s so-called little emperors to be more pessimistic, neurotic and selfish than their peers who have siblings.
Psychologist Xin Meng of the Australian National University in Canberra and her colleagues recruited 421 Chinese young adults born between 1975 and 1983 from around Beijing for a series of surveys and tests that evaluated a variety of psychological traits, such as trustworthiness and optimism. Almost all the participants born after 1979 were only children compared with about one fifth of those born before 1979. The study participants born after the policy went into effect were found to be both less trusting and less trustworthy, less inclined to take risks, less conscientious and optimistic, and less competitive than those born a few years earlier.
“Because of the one-child policy, parents are less likely to teach their child to be imaginative, trusting and unselfish,” Meng says. Without siblings, she notes, the need to share may not be emphasized, which could help explain these findings.
Only children in other parts of the world, however, do not show such striking differences from their peers. Toni Falbo, a social psychologist at the University of Texas at Austin, who was not involved in the study, suggests that larger social forces in China also probably contributed to these results. “There’s a lot of pressure being placed on [Chinese] parents to make their kid the best possible because they only had one,” Falbo says. These types of pressures could harm anyone, even if they had siblings, she says.
Whatever its cause, the personality profile of China’s little emperors may be troubling to a nation hoping to continue its ascent in economic prosperity. The traits marred by the one-child policy, the study authors point out, are exactly those needed in leaders and entrepreneurs.
(Source: scientificamerican.com)
Response and recovery in the brain may predict well-being
It has long been known that the part of the brain called the amygdala is responsible for recognition of a threat and knowing whether to fight or flee from the danger.
Now, using functional magnetic resonance imaging, or fMRI, scientists at the Center for Investigating Healthy Minds at the University of Wisconsin-Madison Waisman Center are watching the duration of the amygdala response in the brains of healthy people when exposed to negative images. How long the recovery takes may be an indicator of personality traits like neuroticism.
Recently published in the journal Social Cognitive and Affective Neuroscience, the study specifically examines how the amygdala responds and recovers from negative stimuli. One of the more primitive parts of the mammalian brain, the amygdala is central to processing emotion, including activating changes in the body that often accompany emotion. In terms of its evolutionary function, this region of the brain is part of a circuit that is key to our sense of fear recognition and alertness to danger.
While the role of the amygdala has been understood and well documented, the time course for the response-recovery process has never been investigated, nor observed, until the recent advance of fMRI analysis methods.
"Past studies looking at the temporal unfolding of emotional responses have focused on reports of emotional experience obtained from interviews and questionnaires," says Tammi Kral, research specialist at the Center for Investigating Healthy Minds and an author of the paper. "This study is different because it looks at the temporal activity in the brain via fMRI."
Through the lens of fMRI, scientists can measure the activation in the amygdala as it reacts to negative stimuli, and the subsequent recovery after the stimulus ends. This study shows that while the initial reactivity of the amygdala does not predict personality traits, a sluggish response-recovery time may be a predictor of neuroticism.
"People’s responses to negative emotional stimuli, and their ability to regulate those responses, can be a major factor in depression, anxiety and other psychological disorders," says Kral. "In the case of depression, the person is often ruminating, perseverating — they’re unable to let go of the negative experience."
The study could have clinical applications because it implies that changing the way people recover from negative occurrences may be a good way to improve their emotional well-being. Research from other groups also supports the idea that individual differences in emotional recovery affect overall well-being.
When the going gets tough, the tough get… more relief from a placebo?
Are you good at coping when life gets tough? Do people call you a straight-shooter? Will you help others without expecting anything in return?
Those personality traits might do more than help you win a popularity contest. According to new University of Michigan-led neuroscience research, those qualities also might make you more likely to get pain relief from a placebo – a fake medicine.
And, the researchers show, it’s not just your mind telling you the sham drug is working or not. Your brain’s own natural painkiller chemicals may actually respond to the pain differently depending on your personality.
If you’re more of an angry, hostile type, they find, a placebo won’t do much for you.
For the first time, the new findings link specific, established personality traits with an individual’s susceptibility to the placebo effect from a sham medicine for pain. The researchers showed a significant link between certain personality traits and how much relief people said they felt when given the placebo – as well as the level of a specific chemical that their brains released.
The work, published online in the journal Neuropsychopharmacology, was done by a team of U-M Medical School researchers and their colleagues at the University of North Carolina and University of Maryland.